The Complete Guide to Landscape Design, Renovation,
by Cass Turnbull
ALL ABOUT HOW TO PRUNE HEDGES
Hedges can be grown in two styles, the formal and the informal.
Formal means that you shear them, informal means that they look
more natural and you selectively prune them to control size and
maintain their good looks.
A big difference between formal and informal hedges is the amount
of time it takes to maintain them. Formal hedges have to be sheared
all over to keep them looking tidy, which may be fast, but must
be done frequently. To control size you cannot miss a year. Informal
hedges can be selectively pruned, and therefore generally need only
touch-ups of unruly branches. They are easier to reduce in size
and look better when reduced this way. Both styles of hedges have
the purpose of providing a natural screen or wall. A formal hedge
(in addition to performing a function) is a style which is good
as a contrast to other plants. Contrast is one of the major elements
of an esthetically pleasing yard. So that, whereas an entirely sheared
yard may look dumb and dull to some people, a perfectly straight
sheared hedge behind your perennial flower bed constitutes valuable
contrast in your yard and is very tasteful.
||To prevent leggy hedges, shear top slightly
narrower than the bottom.
Avoid Leggy Hedges
Avoid creating a hedge with legs. It is considered uncouth to have
such a hedge. You want a hedge that is dressed to the ground, as
in totally formal. Hedges get leggy when sun cannot reach down low,
so that lower leaves are shaded out. The way to prevent this is
to shear your hedge into a slightly pyramidal fashion so that the
top does not shade the bottom. By fall, the top will have grown
back more vigorously than the bottom and it will look more nearly
square. In the colder part of the United States, the pyramidal form
helps prevent damage to the top from heavy snowfall as well.
|Common mistakes are following the ground
level and lowering the hedge as your arms get tired.
|Other errors: two people doing the job; trying to follow a
string tied to the chain link fence.
Creating a Nice Hedge
The major criteria for nice hedges are levelness and straightness.
This is a lot harder to achieve than one might suppose. As people
who have sided a house or laid bathroom tile know, the work may
look even close up, but when you stand back, OOPS!
Mistakes to avoid are (1) following the ground level, (2) lowering
the hedge top as your arms get tired, (3) following last year's
mistakes, cutting just above the old cut, (4) having two people
do it, and (5) following a string tied between two posts or tied
along the adjacent chain link fence.
Some people try using a carpenter's level on a board, or they rig
up a one-dimensional hedge template and move it along. Some pick
a part of their body to cut to. Once Norman the Foreman at the Parks
Department where I worked told the crew to cut at knee level, which,
of course, varied according to whose knees you were talking about.
We sang it to the tune of "She's got Bette Davis Knees."
For very tall and very long hedges, rent scaffolding to help you
cut the hedge perfectly level. The best method I've found for general
hedge cutting is the haircut method: Take a little off at a time
and constantly, frequently stand back and walk around, looking at
your hedge from different angles. Get it right the first time using
loppers--then follow your old cuts the next year using shears or
|For very tall, very wide hedges,
create a "false front," then shear the top from inside.
A hedge needn't, shouldn't, be wider than one person can reach across
on a ladder. If your hedge has gotten very broad, consider serious
reduction. When you drastically reduce the height, or more likely
the width, of your hedge, you will want to do it in the early spring
so that it will most quickly and vigorously hide those ugly bare
branches. Be sure your hedge is the type that will green back up
if pruned hard; many needled evergreens won't. If you are a lazy
gardener and want to shear only once a year, try a tidy cut in June
or July, when it is least likely to promote new shaggy growth. If
you have a truly giant laurel or boxwood hedge with only one side
facing the public, you may want to turn it into a false front by
taking out the unseen inside, or make it into a horseshoe by chainsawing
out the inside. This will make it possible for you to set up your
ladder inside or behind and shear the top.
Have you ever wondered about those giant sheared things on English
estates? How do they do that? That giant holly gum drop? That two-story
yew that looks like elf hat? Well, first off, these plants have
been sheared from the time they were little, every year, so that
they are incredibly bushy and dense right through to the very inside,
and the gardener actually stands or ties the ladder onto the shrub
itself. The plants chosen are slow growing and only need to be done
once a year, usually. Generally the leaves are small.
Which brings us to the point of your laurel or photinia hedge. You
(or someone else) planted laurel or photinia because you wanted
a wall fast. Since these bushes really want to be trees, they oblige
you by growing fast. But they don't stop when they get to the size
you want, they keep growing--fast. They are prone to developing
legs and their big leaves don't look as nice sheared as do fine-leaved
plants. That's what you get for being so impatient.
You will probably want to shear laurel and photinia more than once
a year to keep them looking nice, and after you shear them, go back
and go over everything with your hand pruners and selectively prune
out the ugly stubs and exposed branches. If either of these have
been let go so that you've had to place a twelve-year-old on a plywood
board on top of the hedge to shear the eight-foot expanse on top,
you may rest easier knowing that these incredibly tough plants can
be pruned back hard, which is gardenese for cut way, way back, to
a couple of feet off the ground if you like.
Do not, however, try this radical reduction with your needled evergreen.
It won't work. Most of the conifers and needled evergreens, except
yews, develop the dead zone of bare wood on the inside of a sheared
plant. It gets bigger every year. If you shear deeply into it, it
will not green up again. So, generally speaking, every year your
needled evergreen hedge must get incrementally larger. The qualities
that make good shear material are small leaves, spaced closely together,
slow growing and tough enough to take it.
Some people plant deciduous shrubs for hedges--privet, hornbeams,
and the like. They often need more severe early training than conifers
in order to build a dense bushy framework, especially around the
base. It is even possible to use blooming things like forsythia,
escallonia, quince and camellia. I wouldn't, but I'm prejudiced.
Pyracantha is often used as hedge material and is also valued for
its decorative berries. Your timing may vary in order to retain
as much "show" on these berried and flowering plants as
you can. Do not top your conifer hedge until it reaches the height
you wish it to be. Shear deciduous material all over repeatedly
as it grows to its desired height.
||Avoid cutting into the dead zone on needled
evergreens. If cut deeply, they will not "green back up."
If you have inherited a home with a veritable fortress of hedging
around the perimeter and you want to keep it (I'd take it out and
plant a perimeter of tasteful groupings of shrubs), you may choose
to invest in a pair of electric or gas powered hedge trimmers. The
two most hated pieces of power equipment in the Parks Department
were chainsaws and power hedge shears. That's because they rarely
made it through a group project alive. I always loaded up as many
as I could lay my hands on, so that when one died, I could switch
to a new one. It reminded me of a pony express rider changing to
a fresh horse. I also brought two extra chains for the chainsaw
and some WD-40___ for the blades of the power hedge shears, to use
when they got sticky and wouldn't move.
It's a wise idea to sharpen both of these pieces of equipment before,
during, and after a big job. This is because the amount of physical
effort required increases exponentially with the dullness of the
blade. Also you can get into serious accidents with both these power
tools, the chances of which also increase as you get tired from
forcing dull blades through your shrubbery. People are very reluctant
to stop to rest once they start this equipment, especially when
it's taken thirty-five pulls to get it started, thus ensuring operator
exhaustion from the beginning. Tired people with dull chainsaws
cut their foreheads open (tip kickback); tired hedgers tend to saw
into their thighs. These tools are, on the other hand, useful time
and labor saving devices, if you use the best and the sharpest and
take the time to rest and resharpen. I use my local saw sharpener
a lot, and I keep extra chains on hand. I sharpen things after I'm
done, so that my chainsaw or trimmer is ready when I go to use it
six months later. Electric saws and shears tend to start more easily
than gas powered ones and are much lighter in weight, so you don't
get as tired. Also, you don't get gassed to death by the exhaust
fumes. Be careful with your cord in the rain, however, and don't
cut it and electrocute yourself.
People just don't realize the danger, drama, and high excitement
that waits for them in their own back yards. Now that you know all
about hedges, you are ready for the assault. Let's be careful out
GOOD TO SHEAR
Yew Japanese Holly
Boxwood Box Honeysuckle
OPTIONAL TO SHEAR (Some would argue)
English Laurel Quince
Some Junipers Osmanthus
Hemlocks Evergreen Euonymus
Aborvitae Oregon Grape
DO NOT SHEAR
Deciduous Flowering Shrubs Lilacs
(Forsythia, Deutzia, Roses
Kolkwitzia, Philadelphus, Viburnums
Weigela) Rose of Sharon
Most Barberries Kalmia
Spireas Deciduous Euonymous
CRIMINAL TO SHEAR
Laceleaf Maples Magnolias
Deciduous Azaleas Witch Hazel
Harry Lauder's Walking Stick Dogwoods
Contorted or weeping things Doublefile Viburnums
- Good plants for shearing have small leaves spaced closely together.
They are slow growing and tough. They will not become diseased or
die back as a result of repeated shearing.
- Formal sheared hedges should be level and thin enough for one
person to reach across.
- Make the top of a hedge narrower than the bottom.
- Needled evergreens (hemlock, pyramidalis, etc.) cannot be radically
reduced in width. They will not readily break bud and green back
up, as will most broadleaf plants.
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